Air channeler for reducing wind resistance and method of use

ABSTRACT

An air channeler device is provided for use with a vehicle having a forward and rearward end for reducing wind resistance of the vehicle. The air channeler has an air inlet for positioning within an air stream surrounding the vehicle so that air is received in the inlet as the air stream moves about the vehicle. An air discharge is provided for positioning at a generally central location of the rearward end of the vehicle and has a width that is substantially less than the width of the rearward end of the body so that the air discharge is spaced inward from the edges of the rearward end. An air conduit couples to the vehicle and has a generally tubular passageway that is in communication between the air inlet and the air discharge for directing air from the air inlet through the conduit to the discharge. The air conduit may also be formed into two sections wherein one section is coupled to a movable portion of the vehicle, and wherein movement of the movable portion causes engagement and disengagement of the two sections.

TECHNICAL FIELD

The invention relates generally to methods and devices used for reducingair resistance and drag on a body located within an air stream, andparticularly to those methods and devices for reducing wind resistanceand drag on moving vehicles.

BACKGROUND

When a non-streamline moving body moves through air at high speeds a lowpressure area or “vacuum” usually is created behind the trailing orrearward end of the body. This is particularly true with large vehicleshaving a generally flat or block-shaped rearward end, such as trucktrailers and the like. As a result, the moving body encounterssignificant aerodynamic resistance and drag.

As can be seen in FIG. 1, which shows a streamline or aerodynamic body10 located within an air stream (as indicated by the arrows), there isvery little air compression at the front of the body 10 and very littlevacuum at the rear of the body 10 as air passes smoothly about the outersurfaces of the body 10. Thus, the body 10 moves through the air easilyand with little aerodynamic resistance. In contrast, FIG. 2 shows anon-streamline body 12 with large, flat front and rear surfaces. As airencounters the body 12, a high degree of air compression is observed atthe forward end of the body 12, with a significant vacuum being createdat the rearward end of the body 12. Air rushes into the area of thevacuum to the rear of the body 12, creating turbulent air or vorticesthat increase the drag of body 12.

This effect is a particular problem with large and bulky wheeledvehicles, such as those used for transporting cargo where streamlined oraerodynamic designs are impractical. Such vehicles commonly include manytrucks, tractor-trailers, buses, vans, RV's, locomotives, railcars, andthe like. Because of their design and large size, a significant amountof drag and air resistance is produced. Additionally, such vehiclesusually travel over long distances where even the smallest reduction indrag and air resistance can result in a significant reduction in costlyfuel consumption.

There are numerous methods that have been tried in the past to reducedrag in moving vehicles. And while much work has been done on improvingthe aerodynamics of the front end of vehicles, there has been lessemphasis on improving the rearward or load carrying end, the design ofwhich is oftentimes limited by cargo requirements. Those designs that doexist, however, are often cumbersome and can interfere with the normaloperation and use of the vehicle, such as when opening and closing doorsor accessing the cargo space of the vehicle, thereby making their useimpractical. Many, if not most, of these methods require the use of anairfoil or air-deflecting surface for directing air inwardly from therearward sides of the vehicle to disrupt the trailing vortical air flow.Other methods call for improving the aerodynamic design of the vehicle,such as that disclosed in U.S. Pat. No. 4,257,641.

Improvements are therefore needed for reducing drag and aerodynamicresistance in such vehicles without interfering with the normal use andoperation of the vehicle and which provide a cost effective and easilyimplemented means for doing so.

SUMMARY

An air channeler device is provided for use with a body having a forwardand rearward end and located in an air stream for reducing windresistance of the body. The air channeler has an air inlet forpositioning within an air stream surrounding the body so that air isreceived in the inlet as the air stream moves about the body. An airdischarge is provided for positioning at a generally central location ofthe rearward end of the body and has a width that is substantially lessthan the width of the rearward end of the body so that the air dischargeis spaced inward from the edges of the rearward end. An air conduitcouples to the body and has a generally tubular passageway that is incommunication between the air inlet and the air discharge for directingair from the air inlet through the conduit to the discharge.

In more specific embodiments, the air conduit is formed in at least twosections that are releasably joined together so that the at least twosections can be engaged and disengaged from one another. One of the atleast two sections may also be adapted for coupling to a movable portionof the body, which is movable between first and second positions, andwherein movement of the movable portion between the first and secondpositions causes engagement and disengagement of the at least twosections. A seal may also be joined to at least one of the two sectionsof the air conduit for providing sealing engagement of the two sectionsof the air conduit when engaged with one another.

In other embodiments, various features may be included. For instance, anair damper can be provided that is movable between open and closedpositions for selectively closing off the air conduit to prevent airflow through the passageway. The width of the air discharge may besubstantially less than the distance of the air discharge from the sideedges of the rearward end of the body. The air discharge can be about 12inches or less. The air inlet and air discharge may include oppositeends of the air conduit. Further, a coupling device for coupling the airconduit to the vehicle may be provided.

The air channeler device can also be provided in a vehicle having aforward end and a rearward end for reducing wind resistance of thevehicle. The device has an air inlet for positioning within an airstream surrounding the vehicle so that air is received in the inlet asthe vehicle is moved in a forward direction. An air discharge located ata generally central location of the rearward end of the vehicle andhaving a width that is substantially less than the width of the rearwardend of the vehicle is provided so that the air discharge is spacedinward from the edges of the rearward end. An air conduit is mounted tothe vehicle and has a generally tubular passageway that is incommunication between the air inlet and the air discharge for directingair from the air inlet through the conduit to the discharge.

In still another embodiment, an air channeler device for use with avehicle having a forward and rearward end is provided for reducing windresistance of the vehicle. The device has an air inlet for positioningwithin an air stream surrounding the vehicle so that air is received inthe inlet as the vehicle is moved in a forward direction. An airdischarge for positioning at the rearward end of the vehicle is alsoprovided. An air conduit is coupled to the vehicle and has a generallytubular passageway that is in communication between the air inlet andthe air discharge for directing air from the air inlet through theconduit to the discharge. The air conduit is formed in at least twosections that are releasably joined together so that the at least twosections can be engaged and disengaged from one another. One of the atleast two sections is adapted to be mounted to a movable portion of thevehicle that is movable between first and second positions and whereinmovement of the movable portion between the first and second positionscauses engagement and disengagement of the at least two sections.

A method of reducing wind resistance of a body having a forward end anda rearward end that is located in air stream is also achieved bypositioning an air inlet within an air stream surrounding the body sothat air is received in the inlet as the air stream moves about thebody. An air discharge is provided at a generally central location ofthe rearward end of the body. The air discharge has a width that issubstantially less than the width of the rearward end of the body sothat the air discharge is spaced inward from the edges of the rearwardend. Air is allowed to pass through an air conduit having a generallytubular passageway that is in communication between the air inlet andthe air discharge so that air is directed from the air inlet through theconduit to the discharge.

A method of selectively reducing wind resistance and slowing a movingvehicle having a forward end and a rearward end is also provided. Themethod comprises positioning an air inlet within an air streamsurrounding the vehicle so that air is received in the inlet as thevehicle is moved in a forward direction. An air discharge is provided ata generally central location of the rearward end of the vehicle. The airdischarge has a width that is substantially less than the width of therearward end of the vehicle so that the air discharge is spaced inwardfrom the edges of the rearward end. By selectively allowing air to passthrough an air conduit having a generally tubular passageway that is incommunication between the air inlet and the air discharge so that air isdirected from the air inlet through the conduit to the discharge, windresistance of the vehicle is reduced. Further, by restricting air flowthrough the passageway of the conduit, wind resistance is increased tothereby slow the vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention, and theadvantages thereof, reference is now made to the following descriptionstaken in conjunction with the accompanying figures, in which:

FIG. 1 illustrates air flow about a streamlined body;

FIG. 2 illustrates air flow about a non-streamlined body;

FIG. 3 is a diagram illustrating air flow about a non-streamlined body,wherein the body has an air conduit that passes through the center ofthe body;

FIG. 4 is a side elevational view of a truck trailer incorporating anair channeler device of the invention, and constructed in accordancetherewith;

FIG. 5 is a rear elevational view of the truck trailer of FIG. 4;

FIG. 6 is an enlarged side elevational view of the truck trailer and airchanneler device of FIG. 4, showing further detail of the air channelerdevice;

FIG. 7 is a longitudinal cross-sectional view of the air channelerdevice of FIG. 4;

FIG. 8 is side elevational view of a tractor-trailer combinationincorporating air channeling devices, and shown constructed inaccordance with the invention;

FIG. 9 is a rear elevational view of a truck trailer incorporatinganother embodiment of the invention wherein two air discharges areprovided with the air channeler device, and constructed in accordancewith the invention;

FIG. 10 is a side elevational view of the truck trailer and airchanneler of FIG. 9;

FIG. 11 is a rear elevational view of another embodiment of a trucktrailer incorporating an integral air channeler, and shown constructedin accordance with the invention;

FIG. 12 is a side elevational view of the truck trailer of FIG. 11; and

FIG. 13 is an elevational view of interfacing ports of a conduit of theair channeler of the truck trailer of FIG. 11, and shown constructed inaccordance with the invention.

DETAILED DESCRIPTION

Because of the problems associated with drag and wind resistance ofvehicles having bulky and non-streamline configurations, an airchanneling device is provided to reduce the amount of drag and windresistance these vehicles encounter. As can be seen in FIG. 3, when thebody 12 of FIG. 2 is provided with an longitudinal air conduit or tube14 that passes generally through the center of the body 12, compressedor high pressure air from the forward end of the body 12 passes throughthe conduit 14 and exits at the rearward end of the vehicle. This breaksthe “vacuum” located at the rear of the body 12 and reduces theturbulent or vortical air that otherwise would result, thus allowing thebody 12 to move through the air with less drag and air resistance.

Having a longitudinal tube running through the center of a vehicle,however, would be impractical in most cases and would interfere with thenormal operation of most vehicles. In order to incorporate thosebenefits provided by such a conduit to a vehicle, an air channelerdevice 16 is provided, as shown in FIGS. 4 and 5. It should be notedthat as used herein, the term “vehicle” can include any wheeled bodyused for carrying passengers or cargo, such as automobiles, trucks,trailers, buses, vans, RV's, locomotives, railcars, and,the like, andwhether or not such bodies are self ropelled or require other means forlocomotion. By way of example, the air channeler 16 is mounted to atractor trailer 18, as shown. The trailer 18 is a box-type trailer ofgenerally conventional design that is supported at its rearward end bytires and wheels 20. The rearward end of the trailer 18 terminates in agenerally flat, vertical wall or surface having a generally square orrectangular periphery.

The air channeler device 16 is formed from a generally L-shaped conduit22, although other configurations could be used as well, having agenerally tubular passageway. The conduit 22 may be formed from alightweight plastic, metal or other suitable material. The conduit 22may be rigid or flexible, and may be cylindrical or otherwise shaped andcan vary in diameter or width, but typically will have a width of about12 inches or less, with about 6, 5, 4 and 3 inches being typical. Itshould be noted that as used herein, the term “width” in reference tothe conduits or air passageways discussed refers to the greatestcross-sectional dimension. At one end of the conduit 22 is an air inlet24. While the conduit may have a uniform width or diameter along itslength, the air inlet 24 may have an opening that is greater than theremaining width or diameter of the conduit 22, to facilitate theintroduction of air into the inlet 24. The conduit 22 is coupled ormounted to the undercarriage of the trailer 18 by means of mountingbrackets 26 (FIG. 6) or other suitable fasteners or coupling devices. Inthe embodiment shown, the air inlet 24 is located at a position forwardof the rearward end of the trailer 18. In this case, the inlet 24 islocated forward of the rear wheels 20 of the trailer 18 to minimizeturbulent air flow from the wheels 20. It should be noted, however, thatthe air inlet 24 can be positioned anywhere where air can be receivedfrom the air stream surrounding the vehicle during travel, such as alongthe side surfaces of the vehicle.

The conduit 22 extends rearward from the inlet 24 to the rearmost edgeof the trailer 18. An elbow or bend 28 is provided in the conduit 22adjacent the rearmost edge that essentially divides the conduit into ahorizontal portion 30, oriented parallel to a longitudinal axis of thetrailer 18, and a vertical or upright portion 32. The upright portion 32extends upwards adjacent to and along the rearward end wall of thetrailer 18 formed by laterally swinging cargo doors 34 hinged at 36. Asshown in FIG. 6, the upright portion 32 is mounted to one of the doors34 by brackets or fasteners 38. Preferably, the upright portion 32 islocated at a position so that it does not interfere with the access oroperation of any door handles or locks for opening and securing thedoors 34.

The upright portion 32 of the conduit 22 terminates in an air discharge40. As can be seen in FIG. 5, the air discharge 40 is located at agenerally central location of the rearward end of the trailer.Preferably, the air discharge 40 should be immediately adjacent to or asnear as possible to the rearward end of the trailer 18. The airdischarge 40 has a width or diameter that is substantially less than thewidth of the rearward end of the trailer 18 so that it is spaced inwardfrom the edges of the rearward end of the trailer 18. Preferably, thewidth of the discharge 40 is substantially less than the distance of theair discharge from the side edges of the rearward end of the trailer 18.Because the discharge 40 is centrally located at the center of therearward end of the trailer 18, air is discharged into the area of thegreatest vacuum or lowest pressure. In the embodiment shown, the airdischarge 40 is directed upward, however, the discharge 40 could also beoriented rearward or in other directions, as well.

The conduit 22 is formed into movable and stationary sections 42, 44that releasably join together so that they can be engaged and disengagedfrom one another. The movable section 42 is formed from the uprightportion 32 and elbow 28 of the conduit 22. A portion of the elbow 28projects forward a distance under the trailer 18 and terminates at itsforward end in lip 46 (FIG. 7). Likewise, the stationary section 44 iscomprised of the horizontal portion 30 and terminates at its rearwardend in lip 48, which abuts or faces lip 46 when the sections 42, 44 areengaged. The rearward end 48 of the stationary section 44 terminates ata position forward of the rearmost surface of a rear bumper 49 of thetrailer 18.

A circumferential seal 50 is provided and joined to the rearward lip 48of section 44. The seal 50 is preferably a deformable material, such asrubber, that deforms or compresses to provide a seal between the ends ofthe movable and stationary sections 42, 44 when they are engaged. Theseal 50 may be slightly oversized to provide sealing engagement betweenthe sections 42, 44 should the ends of the sections 42, 44 not be inprecise alignment. Although, the seal 50 preferably provides an airtightseal between the sections 42, 44 when they are engaged, some loss of aircan be tolerated as long as there is substantial air flow through theconduit 22.

A damper 52 is disposed within the interior of conduit 22. The damper 52can be located anywhere along the length of the conduit 22, but ispreferably located near or adjacent to the inlet 24. The damper 52 iscoupled to a solenoid 54 or other actuating device for moving the damper52 between open and closed positions for selectively closing off the airpassageway formed by the conduit 22 to prevent air flow therethrough. Inone preferred embodiment, the solenoid 54 is electrically coupled to thebrake lights of the trailer 18, such as by wires 56, so that when thebrake lights are activated during braking, the solenoid 54 is actuatedto move the damper 52 to the closed position. When the brake lights aredeactivated, the solenoid 54 then returns the damper 52 to its openposition.

The operation of the air channeler device is as follows. When the airchanneler device 16 is mounted to the trailer 18, as has been described,forward motion of the trailer 18 causes air to be introduced into theinlet 24. Air from the inlet 24 passes through the passageway formed bythe conduit 22 where it is exhausted through the discharge 40 at aposition near the approximate center of the rearward end of the trailer18. At speeds where drag and aerodynamic resistance become a factor, theair discharged from air discharge disrupts the low pressure or vacuumarea and the turbulent air that would otherwise be formed without theair channeler, and thereby reduces the drag of the trailer.

During braking operations, application of brakes of the trailer causesactivation of the solenoid 54, which is electrically coupled to thetrailer's brake lights. The solenoid causes the damper 52 to pivot tothe closed position, effectively closing off the passageway formed bythe conduit 22. Because air is prevented from being discharged throughthe air discharge 40 to disrupt the low pressure or vacuum area to therear of the trailer, drag and aerodynamic resistance of the trailer areincreased, thus facilitating slowing of the vehicle during brakingoperations. When the brakes are released, the damper 52 is opened bydeactivation of the solenoid 54.

The air channeler device does not interfere with the normal operationand use of the trailer. Thus, to access the interior of the trailer 18,the cargo doors 34 are merely opened in a normal fashion. Because theair channeler 16 is formed into two sections, the movable section 42,which is mounted to one of the cargo doors, disengages from thestationary section 44 and is moved out of the way when the cargo door isswung open. When backing into a loading dock or otherwise, the bumper 49protects the stationary section 44, which is located at a positionforward of the rear surface of bumper 49 and out of the way.

When the cargo door 34 carrying the movable section 42 is closed, themovable section 42 engages the stationary section 44 and stays engagedas long as the door 34 remains closed. The circumferential seal 50facilitates sealing engagement between the two sections 42, 44 andallows for slight misalignment of the two sections 42, 44.

Referring to FIG. 8, another embodiment is shown wherein a second airchanneler device 58 is mounted to a tractor 60 for pulling the trailer18. The device 58 is similar to the channeler device 18, however, theair inlet is located at the front of the tractor 60, in this case at ornear the front bumper, and the discharge 64 is located at a position tothe rear of the tractor 60. This reduces air compression at the front oftractor 60, while disrupting the low pressure area formed in the area 66between the front of trailer 18 and rear of tractor 60.

FIGS. 9 and 10 show still another embodiment of the invention. As shown,an air channeler device 68 is mounted to the rear of the trailer 18 andis provided with two movable sections 70, 72, each mounted to the twolaterally swinging cargo doors 74, 76 of the trailer 18. The dischargeof sections 70, 72 are each located at a position as near as possible tothe center of the rearward end of trailer 18. Because the sections 70,72 are located laterally to either side of the center between cargodoors 74, 76, however, access to the centrally located locking mechanism78 is provided. The movable sections 70, 72 of the conduit each engage amanifold 80 of the stationary section 82. An air scoop or inlet 84 isprovided for introducing air into the channeler device 68. In theembodiment shown, the inlet 84 is located at a position behind the rearwheels of the trailer. Operation of the device 68 is generally the sameas that described for air channeler 16.

FIGS. 11 and 12 illustrate another embodiment of the invention whereinthe channeler device is integral with the trailer 86. The walls of mosttractor trailers, particularly those insulated trailers used fortransporting refrigerated goods, have a sufficient thickness wherein anair channel or passageway 88 can be formed therein between the inner andouter skin of the sidewalls 89. The conduit 88 can be formed in each ofthe trailer sidewalls 89. As shown in FIG. 12, the conduit 88 has an airinlet 90 located at the upper forward portion of the trailer 86,although the inlet 90 could be located in other positions as well thatare likely to encounter air flow. The passageway 88 extends the lengthof the trailer 86 and opens at discharge 92 located at the end edges ofthe sidewall 89.

The trailer 86 is provided with laterally swinging cargo doors 94, 96that are coupled to the sidewalls 89 of the trailer 86 by hinges 97.Formed in each of the cargo doors 94, 96 is a passageway or conduit 98.The cargo doors 94, 96 are similarly constructed to the sidewalls 89 andhave a sufficient thickness to accommodate the conduit 98. An inlet 100is formed in the portion of the doors 94, 96 that interface with theedges of sidewalls 89 so that the inlet 100 is in communication withdischarge 92. As shown in FIG. 13, the inlet 100 is similarly configuredand shaped to correspond to the discharge 92. Circumferential seals 102,104 formed from a compressible material surround the discharge 92 andinlet 100 so that sealing engagement is achieved when the doors 94, 96are closed.

The conduit 98 formed in the cargo doors 94, 96 extends the width of thedoors and terminates in an air discharge 106. The discharge 106 islocated as near the center of the rearward end of the trailer 86 aspossible.

The operation of the air channeler device integrally formed with trailer86 is similar to that of the channeler 16. When the doors 94, 96 areopened, the inlet 100 and discharge 96 disengage. When the doors 94, 96are closed, the inlet 100 and discharge 96 engage to provide acontinuous conduit for airflow to the discharge 106.

The invention has several advantages. The air channeler provides a meansfor reducing drag and aerodynamic resistance. This provides better fuelefficiency and greater gas mileage of most vehicles, which is importantas fuel prices continue to rise and because of environmental concerns.In addition to greater fuel efficiency, because the air channelerdisrupts the turbulent air flow behind the vehicle, improved stability,handling and safety of the vehicle are achieved. Maintenance costs arealso reduced as wear on items such as wheel bearings and relatedcomponents is decreased. Further, safety is also increased for thosefollowing or passing vehicles incorporating the air channeler of theinvention than would otherwise occur in the wake of the same vehiclewithout the device. The device also improves or enhances acceleration orslowing of the vehicle, such as during braking operations, by providinga means for selectively, opening and closing the air duct to decrease orincrease drag.

The air channeler is simple in design, easy to install, can bemanufactured and installed at low cost, and can be used on almost anyvehicle without significant after-market modification. The device isless cumbersome than prior art designs and does not interfere with thenormal operation the vehicle. The device can also be integrallyincorporated with the vehicle.

The following example serves to further illustrate the invention.

EXAMPLE

An air channeler device was installed on a utility trailer of atractor-trailer combination in a similar configuration to that shown inFIGS. 4 and 5. The device was formed from PVC pipe having a three-inchdiameter, and utilized an air inlet having a six-inch diameter. Aftertwo consecutive calendar quarters, a second air channeler device ofsimilar construction was employed with the same tractor unit, in asimilar configuration to that shown in FIG. 8. Gas mileage statisticsboth with and without the air channeler devices are presented in Table 1below.

TABLE 1 Year 1 Year 2 Year 3 Year 4 Year 5 Quarter Gal @ Mile/Gal Gal @Mile/Gal Gal @ Mile/Gal Gal @ Mile/Gal Gal @ Mile/Gal 1^(st) Qtr. 38,837@ 5.80 35,329 @ 5.71 38,125 @ 5.15 33,835 @ 5.05 28,588 @ 6.16* 2^(nd)Qtr. 42,594 @ 5.85 37,296 @ 5.60 37,519 @ 5.65 38,217 @ 5,78 33,068 @6.72* 3^(rd) Qtr. 36,281 @ 5.57 31,694 @ 6.06 29,781 @ 5.77 34,753 @5.75 4^(th) Qtr. 33,752 @ 5.94 36,841 @ 5.95 35,173 @ 6.00  31,600 @6.09* *Air channeler installed.

While the invention has been shown in only some of its forms, it shouldbe apparent to those skilled in the art that it is not so limited, butis susceptible to various changes and modifications without departingfrom the scope of the invention. Accordingly, it is appropriate that theappended claims be construed broadly and in a manner consistent with thescope of the invention.

We claim:
 1. In a vehicle having a forward and a rearward end, an airchanneler device for reducing wind resistance of the vehicle, the devicecomprising: an air inlet for positioning within an air streamsurrounding the vehicle so that air is received in the inlet as thevehicle is moved in a forward direction; an air discharge located at agenerally central location of the rearward end of the vehicle and havinga width that is substantially less than the width of the rearward end ofthe vehicle so that the air discharge is spaced inward from the edges ofthe rearward end; and an air conduit integrally formed with the vehicleand that has a generally tubular passageway that is in communicationbetween the air inlet and the air discharge for directing air from theair inlet through the conduit to the discharge.
 2. The air channelerdevice of claim 1, wherein: the air conduit is formed in at least twosections that are releasably joined together so that the at least twosections can be engaged and disengaged from one another.
 3. The airchanneler device of claim 2, wherein: one of the at least two sectionsis mounted to a movable portion of the vehicle that is movable betweenan open and closed position and wherein movement of the movable portionbetween the open and closed position causes engagement and disengagementof the at least two sections.
 4. The air channeler device of claim 2,further comprising: a seal joined to at least one of the two sections ofthe air conduit for providing sealing engagement of the two sections ofthe air conduit when engaged with one another.
 5. The air channelerdevice of claim 1, further comprising: an air damper movable betweenopen and closed positions for selectively closing off the air conduit toprevent air flow through the passageway.
 6. The air channeler device ofclaim 1, wherein: the width of the air discharge is substantially lessthan the distance of the air discharge from the side edges of therearward end of the vehicle.
 7. The air channeler device of claim 1,wherein: the air inlet and air discharge include opposite ends of theair conduit.
 8. The air channeler device of claim 1, wherein: the airdischarge has a width of about 12 inches or less.
 9. The air channelerdevice of claim 1, wherein: the vehicle is a trailer, and wherein atleast a portion of the air conduit is formed in a wall of the trailer.10. The air channeler device of claim 1, wherein: the vehicle is atrailer having at least one sidewall and a rear door movably coupled tothe at least one sidewall between an open and closed position; whereinthe air conduit is formed in at least two sections, one of the at leasttwo sections being formed in the sidewall and the other being formed inthe rear door, and wherein movement of the rear door between the openand closed position causes engagement and disengagement of the at leasttwo sections.
 11. In a vehicle having a forward and a rearward end, anair channeler device for reducing wind resistance of the vehicle, thedevice comprising: an air inlet for positioning within an air streamsurrounding the vehicle so that air is received in the inlet as thevehicle is moved in a forward direction; an air discharge forpositioning at the rearward end of the vehicle; and an air conduitintegrally formed with the vehicle, the air conduit having a generallytubular passageway that is in communication between the air inlet andthe air discharge for directing air from the air inlet through theconduit to the discharge, the air conduit being formed in at least twosections that are releasably joined together so that the at least twosections can be engaged and disengaged from one another; and wherein oneof the at least two sections being formed in a movable portion of thevehicle that is movable between first and second positions and whereinmovement of the movable portion between the first and second positionscauses engagement and disengagement of the at least two sections. 12.The air channeler device of claim 11, further comprising: a seal joinedto at least one of the two sections of the air conduit for providingsealing engagement of the two sections of the air conduit when engagedwith one another.
 13. The air channeler device of claim 11, furthercomprising: an air damper movable between open and closed positions forselectively closing off the air conduit to prevent air flow through thepassageway.
 14. The air channeler device of claim 11, wherein: the widthof the air discharge is substantially less than the distance of the airdischarge from the side edges of the rearward end of the vehicle. 15.The air channeler device of claim 11, wherein: the air inlet and airdischarge include opposite ends of the air conduit.
 16. The airchanneler device of claim 11, wherein: the air discharge has a width ofabout 12 inches or less.